Control valve



Nov. 2l, 1944. H, R ELLlNwoQD 2,363,235

CONTROL VALVE Filed Jan. 25, 1941 4 Sheets-Sheet 2 l Zffaz 5. jza. 4.

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Nov. 2.1,' 1944. H. R. l-:LLlNwooD CONTROL VALVE Filed Jan. 25, 1941 4 Sheets-Sheet 5 Z .2\ \m M. n Q IW@ Q@ www M.. N j m Nov. 21, 1944. H. R. ELLINWOOD CONTROL VALVE Filed Jan. 25, 1941 4 sheets-sheet 4 lrmmz Jiayllizz Parental Nov. 21, 1944 CONTROL VALVE Herman Ray Ellinwood, Burbank, Calif., assigner to Adel hecision Products Corp., Burbank, Calif., a corporation of California Application January 25, 1941, Serial No. 375,943

(Cl. (io-52) J Claims. My invention has for its primary object the provision of a new and eilicient valve which is especially designed for controlling the operation of hydraulic jacks or like actuators for the landing gear, landing flaps, brakes, cowl flapabomb doors, gun turrets, and other fluid actuated or controlled devices of an airplane, in that it is characterized by extreme compactness and small size, minimum weight, simplicity of design, symmetry; balance and reliability of performance.

.An important object of my invention is to provide a valve which Will permit of selective movement in either direction of the iiuid operated pistor or plunger of a hydraulic jack under precise control of the operator, and automatically return to a neutral or predetermined position following a predetermined movement of the piston, andcause said piston to become fluid locked and thereby held in the'` position gained until the lnext operation of the valve whereby to alord a greater nicety of control and selectivity of operation of the piston with a minimum of manual actuation of and attention to the valve.

Another object of my invention is to provide a hydraulic control valve of the character described wherein a plurality of valve 'members may be selectively actuated by means of a manually movable cam shaft which is also subject to operation as a fluid driven piston for the purpose of restoring the valve assembly to a neutral or predetermined positionl the cam shaft piston being also manually movable to effect the return of the valve to neutral, Where-by the iull operation of the valve may be manual or -part of the operation manual and the remainder automatic to thereby attain the desired nicety of control, selectivity of `operation and readiness attention to operation, as well as with a p-roper coordination of the airplane control elements which respond to actuation of said valves. For example, to set the landing gear, the operator moves the handle of the appropriate valve a predetermined extent as indicated, and may immediately release the handle inasmuch as the landing gear jack then completes its operation and the handle and valve will return to neutral automatically when the landing gear is set. Having once moved the handle to a predetermined position, the operator is free to immediately operate another valve, for example, for the landing flaps, and another, and so on in like manner, so that in a shorter period of time than heretofore and with less manipulation the desired hydraulifor' selective operation following each predetermined operation of the valve.

The importance of the return to neutral provision of my improved valve will be apparent when it is understood that modern airplanes, particularly the military type, sometimes employ ten or more hydraulic jacks or similar devices each controlled by a valve.` In certain operations of a modern airplane it becomes necessary of time a plurality of the control valves either for the operators to manipulatein a short period substantialy simultaneously or in rapid sequence;

hence the automatic return to neutral function achieved by my valve makes Oit unnecessary for the operators to manually return the valves to neutral position and therefore the vdesired control. of the plane may be effected with a saving in time and manual effort, and a minimum of cally .operated and controlled elements of the plane may be operated and controlled lin such sequence andmanner as to insure the best possible manipulation and control of the airplane and its component parts and accessories.

A further purpose of my invention is to Vprovide a control valve such as described in which a 4simply constructed and easily machined body membermade of standard bar stock is provided for containing a plurality of valves of simple form and arrangement subject to ready installation and removal. These valves are also subject to selective operation by means of a novel cam shaft, likewise of simple form and adapted to be made with a minimum of machining and tooling. Thus it is seen that the valve assembly may be' inexpensively and quickly produced in quantities and in an extremely compact form, light as to weight and reliable in performance.

Yet another purpose of my invention is to pro'- vide in a control valve a novel and efficient operating mechanism for selectively manually controlling the operation of the plurality of valves in the assembly and the cam-shaft-piston Whereby the latter will also respond automatic ly to fluid pressure and return fthe control val es,

to neutral following a predeterminedV operation thereof. u

An additional object of 'my invention is to provide a control valve wherein a novel arrangement yof simple bores in a. `body block, with singl-e valves and control members in each of certain of said bores and other of lthe bores serving as 'passages,.l makes possible an eflicient and compact hydraulic control having, for example, in

the body block two high pressure valves controlactuator cylinder to the pump reservoir, a high pressure by-pass valve permitting a series hookup of two more selectively operable valve assemblies of myinvention in the-one circuit with one pump, a high pressure iluid lock-out check valve for maintaining the high pressure uid in the actuator cylinder, two cam shaft operating `valves for permitting iiow of high pressure iluid to opposite ends of the cam-shaft-piston automatically when the Jack piston reaches the ends of its strokes, `whereby to return the valves to neutral position and open the high pressure by-pass valve; two check valves controlled by means of a manually operated device for shifting the camshaft-piston and operating to relieve the low pressure iluid to the pump `reservoir from opposite ends oi' the cam-shaft-piston unit, and a thermal expansion relief valve for relieving iluid from the valve assembly to the pump reservoir, when the uid attains an excessive pressure from overheating.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the invention is carried into eiIect as illustrated by way of example in the accompanying drawings, in which:

control another Jack F which may be operated by pressurefluid from the pump B, said two valves as here shown being constructed so that when one is operated the other is automatically cut out of the system and vice versa, whereby each will respond to operation at any time except when one thereof is being operated.

The valve D here shown includes a small compact and generally rectangular body I which may be conveniently made from suitable bar stock and easily tooled to provide the necessary passages, ports and spaces for accommodating the valves and other componentsof the valve assem bly.

The valve is constructed as best shown in Figs. 3, 4, andv 6 to receive the high pressure fluid from the pump B, as by means of a high pressure line 2 connected by means of a tltting 3 to a high pressure intake passage I. Passage 4 leads downwardly from the approximate center of the upper side of the-body I, a short distance and then extends laterally as at l (see Fig. 6) through one face of the body, said passages being formed by two simpleright angular intersecting Fig. l is a diagrammatic view of the valve and ahydraulic jack system as in neutral position:

Fig. 2 is a diagrammatic View similar to Fig. l with the valve in one of its operative positions when the valve is in which the piston of the jack is moved in one direction:

Fig. 3 is a perspective view of my improvedk valve looking toward the rear face thereof;

Fig. 4 is a perspective view looking toward the front face of the valve;

Fig. 5 is a vertical sectional view on the line 8-5 of Fig. 4;

Fig. 6 is a cross sectional view on the line 8"-5 of Fig. 4; a

Fig. 7 is a fragmentary sectional view vtaken on the line l-I of Fig. 8;

Fig. 8 is a fragmentary sectional view taken on the line 8 8 ofFig. 6; Fig. 9 is a horizontal sectional view taken on the line 9--9 of Fig. 5:

Fig. 10 is a perspective view of a part of the manually operable control means for the valve;

Fig. 11' is a sectional view on the line II-II of Fig. 4, showing one of the relief valves:

Fig. 12 is a sectional view taken on the line l2-I2 of Fig. 13 showing the thermalrelief .Vflve 4 Fig. 13 is a horizontal sectional view taken on theline I3I3 of Fig. 5. Y

Referring now more speciilcally to the accompanying drawings, and particularly to Figs. 1

- and 2, which show diagrammatically one embodiment of my valve as when employed for con-v trolling the operation oi' a hydraulic jack, A designates a fluid reservoir, B a hydraulic pump connected with the reservoir, C a hydraulic jack such as may bey employed for operating the land-` bores which are typical of the port and passage arrangement throughout my valve. The outer end o*e the passage t' is closedby means of a remf /able anged cup 5 (see Figs. 6 and 13) in which a spring loaded uid locking ball check valve 5 is socketed so as to normally engage a seat 1. Check valve 6 opens responsive to high pressure uid in the ,passages 4 and 4 and closes when the high pressure iluid is by-passed as shown in Fig. 1 and as will be more fully explained hereinafter.

High pressure passages 8 and 8 lead from points oi' communication with opposite sides of the branch intake passage i' beyond the valve seat 'I as shown in Fig. 13. to valve chambers or passages 8' andS. Spring loaded high pressure valves I0 and II mounted in chambers 8" and 9' are urged toward their seats I t' and. II' in the lower ends of said chambers by means of their springs I2 and i3 and the fluid (see Fig. 5).

' The chambers B' and 9 are formed as straight bores (see Fig. 5) leading from the top of the body and closed at their upper ends by means of removable plugs I2' and I3' in which the springs I2 and I3 are socketed.

Jack operating passages I4 and I5 extend downwardly from beneath the seats I0' and II and then laterally as at I 4' and I5' through one face 0f the valve as best shown in Figs. 5 and 13. At their outer ends the passages Il' and I5 are provided with ilttings I6 and I'I for connection with opposite ends of the cylinder of the jack Cv asby means of the lines I8 and I9v (Figs. 1, 2, 3, and 13). Lines I8 and- I9 and thebranches Il and I5' serve to conduct high pressure uid to and also return low pressure iluid from the jack. The low pressure fluid returns into passages 20 and 2i formed adjacent the passages I4 and I5 and their contiguous chambers 8' and 9' as seen in Fig. 5, the portions or branches Il' and I 5' communicating alike with return passages 20 and 2i and passages I4 and I 5, due to the intersection of the bores which form the passages Il, I5, Il', I5', 20 and 2|.

Fluid returned to the passages 20 and 2I will pass through valveseats 20' and 2|' in the lower ends of said passages, and through ports 22 and 23 into a cam shaft passage 2 4 which extends longitudinally through the valve body I `valve .E coupled with valve D and adapted to (l=ig. 5)1 as a straight bore closed at its ends by aacaass means ofremovab'ie heads 25 and serves as a' cylinder.

Low pressure or return valves 23 and 21 in the return4 passages 20 and 2I are urged against the seats 26 and 2I' by means of springs 23 and '23 socketed in removable plugs 34 and 3| which close the upper ends of the return passages.' These plugs as well as plugs I2' and-I3 and cup 5 provide for ready removal and replacement of the valves, seats, spring,`etc. associated with said plugs and cup.

Fluidreturned to the cam shaft passage 24 as aforesaid passes out through a passage 32 having a fitting 33 at its outer end providing for connection with a return line 34 leading backto the reservoir `A.

In the lower part of the high pressure intake passage 4 is an annular valve seat 35 for a high pressure by-pas's valve 36 which is urged against said seat by means of a spring 31socketed in the fitting 3. A by-pass passagev 33 leads from the lower end of the high pressure intake passage at a point below the valve seat 35 and is provided at its outer end with a fitting 39 by means of which a. by-pass line 40 may conduct operating uid to the valve E for operating jack F. When by-pass valve 36 is closed the high pressure fluid opens the check valve 6 and passes into valve D whereby jack C may be operated. When the by-pass valve 38 is opened, high pressure fluid from the vintake passage 4 flows into by-pass passage 3e and out through line 40 to valve E. As the opening. of this by-pass valve reduces the pressure of the operating fluid, the `sp'ring loaded check valve 6 closes and thereby shuts off the ilow of operating fluid to valve D.l Valve 6 also serves to create a iiuid lock for the piston in the jack C so that said piston will be maintained in a predetermined position.

The high pressure valves vIIJ and` Il, the low pressure or fluid return valves 26 and 21 and the by-pass valve 36 are adapted to be operated and controlled by means of a cam shaft 4I mounted in the cylinder passage 24 in the body I as shown in Figs. 5, l and 2. In the present embodiment this cam shaft is reciprocable and is adapted to be both manually and automatically shifted for actuating said valves. Each of valves III, II, 26, 21 and 36 is of the samev construction and includes a short pilot stem 42 slidably supported on and extending below the valve seat therefor. Pusher said valve stems.

. At its ends the cam shaft is provided with piston packing means 44 and `45 whereby the shaft will operate as a piston responsive to hydraulic pressure against its ends. Between its ends the cam shaft is reduced to provide a space in the passage 24 whereby the iluid return ports 22 and 23 may communicate with the outlet passage 32 which latter` opens to said space.

Approximately centrally of the ends of the cam shaft is a cam portionA 46 for effecting the opening and closing of the by-pass valve 36 through the push rod 43 and stem 42 thereof. 'On onpo` site sides of the cam portion 46 the cam shaft is provided with cam portions 41 and 46 for actuating the push rods 43 and stems 42 associated with the high pressure' valves In and II respectively, and adjacent the ends of said camshaft are cam portions 49 and 56 for actuating thepush rods and steinsto effect the operation of the return or low pressure valves 26 and 21 respec- I tively.

When the cam shaft is in neutral position the push rod 43 for the by-pass valve 36 rests on the high dwell point of the cam portion 46, there.. by holding said valve open, whereas the push rods 43 for the two high pressure valves I0 and Il and the two low pressure valves 26 and 21 are spaced from contact with their respective cam portions 41 and 48 and 49 and 50, so that said high pressure and low pressure valves are closed. This neutral condition of the control valves causes the operating uid from the pump to'by-pass through open valve 36 to another valve such as the one E shown in Fig. 1, orA as is obvious, back to the pump reservoir.

When it is desired to extend the jack plunger,

the cam shaft is shifted from neutral position tral position will bring about opening of high pressure valve I0 and low pressure-valve 21 and the closing of valves Il, 26 and 36"whereby to retract the jack plunger.

To provide for operating the cam shaft Ia .i

means M as here shown including a pinion 5I is mounted in a recess or bore 52 formed in the body I so as to intersect the cam shaft passage 24 (Fig. 6) and form an opening 52 whereby the pinion may be meshed with rack teeth 53 on the camshaft. A rotary shaft 54 is journalled in a counterbore 53' of the recess or bore 52 and drives the pinion 5I. This rotary shaft extends out through a cover or closure cap 55 removably fitted on the outer face of the body so as to form with said recess 52 a uid tight chamber 56 for a purpose to be hereinafter described. The outer end of the shaft is equipped with a suitable handle 51 by means of which the shaft may be rotated in either direction for driving the pinion 5I and thereby shifting the cam s haft 4I. l

I havefound that it is desirable for reasonsk hereinbefore pointed out to eiect an automatic return to neutral of the cam shaft controlled valves and therefore provide for` automatically shifting the cam shaft for such purpose when the jack plunger reaches predetermined positions. This return to neutral provision also makes possible an automatic fluid locking action of the jack plunger so that it will be maintained in the desired position by means of the fluid trapped in the ends of the jack cylinder coincident with the aforesaid return to .neutral operation.

For the purpose of automatically returning the valves to neutral, cam shaft operating passages 58 and 59 are formed in the'body to extend parallel with and spaced laterally from the returnA passages 20 and 2| and are communicated with said return passage through ports 58 and 59 at points above the return valves 26 a'nd 21 as shown in Figs. 11 and l2.` Thepassages 58 and 59 are closed at their Iupper ends by means of plugs 60 means 61 and 88. Valves 85 and 68 are tensioned to open at the increased pressure attained at the ends ofthe strokes of the Jack plunger. The portions of the passages 58 and 59 below the checkA valves 65 and 65 are communicated with the ends of cam shaft passage 24 by means of passages 59 and 10, best shown in Fig. y11. As a result of this arrangement of the passages 58 and 59 and associated passages,

it is seen with reference to Fig. 2, that when return or low pressure valve 21 is closed and high pressure fluid flows past open valve and to the jack for extending the jack plunger, the high pressure vuid is also -presentin the portion of low pressure passage 2| above the valve 21 therein and therefore is eective through the ports 59 and 62 to open the check valves 66 responsive to a pressure ibuild-up or increase which will occur when the jack plunger reaches the end of its stroke. Thusit is seen that check valves 85 and 55 controlling-the operation of the cam shaft asa piston are automatically opened when the plunger of the jack reaches the ends of its strokes and the -pressure builds up in the system as aforesaid. When check valve 58 opened the operating pressure fluid is eective through passages 59 and 19 to reachf'the right end of the cam shaft as shown in Flgr2 and the cam shaft will then move to the left andoperate the valves to return them to neutral position shown in Fig. l.l i

Before the cam shaft 4| can be operated it is necessary` that the lfluid at least at one end thereof be relieved and this is accomplished as here shown by means of-two spring loaded ball check valves 1i and 12 controlled by the oper' ating means M as will now be described.

As shown in Fig. 9 low pressure return pas-- sages 13 and 1li lead. from the lower ends of passages 58 and 59 to bores 15 and 18 formed in the body i adjacent and on opposite sides of theshaft 54'. Bores'li and 16 open to a recess 11 formed in `an adjacent face of the body i, through which recess spring loaded check valves 1| and 12 are inserted into position for operation in said bores. 'Passages 18 and 19 lead from the inner ends of bores 15 and -15 to the recess 52. As the recess 52 is communicated by means of the opening 52' with that p'art of the cam shaft cylinder or passage 24 which is between the ends of the shaft and in communication with the .fluid return passages 32 and line 34 leading to the reservoir A, it is seen that when one of the check valves 1| `and 12, for example; valve 1|, is opened uid'will ow from the left end of the cylinder as seen in Fig. 2 through passage 69 into the passage 58'and from thence through passage 13, open check valve 1|, passage 18, recess 52, andv opening 52 into cam shaft passage 24 and out through return passage 32 and -line 34 to 'reservoir A. This will vent the passage 24 so that the. cam shaft may be movedtothe left from position shown in Fig.

portion 86 of shaft 54 and abuts the corresponding ends of the sleeve 85 and end portion 88 to the drive pins 8| and the cam surfaces89. This tothe shaft 54 for rotation in the chambe 55 and carries peripheral drive pins 8| engaging in cam notches 82 in a camand drive `ring 83 conthe sleeve |35l where it'extends through the closure cap 55 to provide a fluidv tight seal. A

helicalspring 88 is mounted onthe tubular end' cam action takes place as the cam surfaces 89 move relative tothe drive pins 8| with the initial movement of the handle 51, and results in the sleeve 85 and ring 83 being forced axially f inward while the sleeve is also turned said predetermined` extent. This inward movement of the cam ring causes pusher rods 99 and 9| (see Fig. '10) bearing against said ring to be extended and open the check valves 1| and 12 simultanereturn toneutral is desired.

AThe `anaal turning' ofthe handle 51, sleeve atl and ring 83 which effects the cam action and results in the opening of both check valve 1| and 12, also disposes an arcuate cam segment 92 carried by said ring, so that one of the pusher rods will ride on said cam segment while the other is clear thereof and although both pusher rods are extended sufficiently to open the check5 valves 1| and 12 by the action of the cam surfaces 89. said rods will remain one on and one oi the cam segment 82 until the cam shaft 41;,A shaft 54, handle 51,and associated parts dre returned to neutral. I l

when theV handle s1 is moved in either direc;

tion past the point where the two check valves 1| and 12 open, or in'other words about seven degrees of arc, the drive pins 8| engage certain of the side edges 82'y of notches .82 and thereby provide for turning the disk 80 andv shaft 54 so that drive pinion 5| through rack teeth 53 will shift the cam shaft 4|, forl example, from position shown` in Fig. 1 to position shown in Fig. 2. whereby to extend the piston of the jack C. During the rotation of shaft 54 to effect an operation of the jack, the cam segment 92 on the drive ring 83 is disposed so that the one of the pusher rods 9|) and 9| which'rests on said segment will be spaced a greater distance iromthev endsA of said segment, or in other words, from the fiatl portion .92' vof the ring 83 on which portion the other pusher rod is engaged. This setting of said pusher rod further inward-on the cam segment is important because when the handle 81 is resion exerts an outward push on 4the ring 83 whereby the cam surfaces 89 are urged against drive pins 8| and cause the ring 83, sleeve 85, and

, handle 51 to move .toward neutral position the nected by means of lweb 84 with a vdrive sleeve same extent as originally moved to simultaneousl Vly open valves 1| and 12, while at the same time moving the ring 83 and sleeve 85 axially outward sufficient to release the pusher rods 98 and 9| and allow valves 1| and 12 to close. However, it is desired-.to maintain one pusher rod in position to open its ,associated valve and the other in manually or hydraulically returned to neutral. It is therefore seen that movement of the cam segment 92 through the action of cam surfaces 89 and pins 8|, (approximately seven degrees of and 9) to the right of position thereof shown in which they were manually moved until either arc) will not move the cam segment 92 on the ring out of position clearing the one of the two pusher rods 99 and 9| which was initially disposed on said segment with the initial (seven degrees) movement of the handle 51 and ring 83,

and said one pusher rod will maintain its associated one of the two check valves 1| and 12 open to relieve the fluid from the end of the passage 24 toward which end the cam shaft 4| must be moved to return to neutral position under hydraulic pressure.

The retention of the cam shaft 4| and its associated manually operable means in its operative and neutral positions is assured by means of detent mechanism N disposed in the recess 11.

This detent mechanism includes a cam member 94 (Figs. 6, 'Z and 9) keyed on the shaft 54 and having angularly related flat and contiguous surfaces 95, 96 and 91 adapted to bear upon a leaf Aspring 98. Spring798 issecured inthe recess 11 tentional movement of the valve mechanism out of predetermined position. However, the detent means will readily. yield to manual effort applied through the operating mechanism M and when the cam shaft is hydraulically actuated. Moreover this datent means will serve as an actuator to assist the return of the cam shaft to neutral position, inasmuch as the action of the spring 99 against the corners 98' between the flat surfaces 95, 96 and 91 of the cam 94 .will produce a leverage suiiicient to turn the shaft 54 and shift the cam shaft.

.A spring loaded thermal expansion relief valve i 99 is seated in a passage |00 therefor inthe body One end of passage |99 opens into high pressure intake passage 44' as shown in Figs. 12 and 13 beyond valve 6 and adjacent the juncture of passages 8, 9 and 4'. A plug |9| closes the other end of the passage |90. A vent passage |92 leads from thepassage `|90 into the central part of cam shaft passage 24 whereby fluid relieved yby the valve 99 will return .to the reservoir .through passage 32 and line 34. The valve 99 isV tensioned to open at above pressures required for operating valves 65 and 66 and therefore opens Fig. 4 and thereby turns the sleeve 85 clockwise relative to shaft 54 a short distance, say seven degrees of arc, before `the shaft commences to turn. During this initial movement of the handle 51 and sleeve 85 the'V-shaped cam surface 89 on the ring 83 carried by sleeve 85 is moved rel- ,ative to the drive pins 8| (Figs. 6, 9 and 10) which latter cannot move due to the fact that all valves controlling the flow of fluid relative to the cam -shaft passage 24 are closed and nuid is lockedv therein so as to prevent movement of the cam shaft 4|, pinion 5|, shaft 54, disk 89 and pins 8| on said disk.` The cam ring 83 in turning as 'aforesaid will, due to the cam action between pins 8| and cam surface 89, be forced axially inward against the action of the spring 88 and in so moving will extend the push'rods 90 and 9|! and simultaneously open (see Fig. 9) the check valves 1| and l2. The'opening of the valves 1| and 12 releases the uid lock on the cam shaft and uid is subject to discharge from both ends of passage 24 through passages 69 and 19, passages 58 and 59, passages 13 and 14, open check valves 1| and 12, passages 18 and 19, opening 52 into open portion of passage 24 between the ends of the cam shaft 4I, and thenceback to reservoir A through the passage 32 and return line 34.

When the valves 1| and 12 are opened simultaneously further movement of the handle 51 to the right causes side edges 82' of the notches 82 in the drive and cam ring 83 to engage drive pins 'l 8| and thereby rotate the disk 80 and shaft 54 in a clockwise direction so that the pinion 5| engaging rack teeth 53 will shift the cam shaft 4| to the right of the position shown in Fig. 1. The fiat face 91 of the detent member 94 on shaft 54 will engage spring 98 to stop the manual operation when the cani shaft reaches the position shown in Fig, 2. Y

The cam shaft 4| in moving to the right from l position shown in Fig. 1 to position shown in Fig. 2 disposes the cam portion 46 in position to allow the spring urged by-pass valve 36 to close and at the same time the cam portions 48 and ,49 operate toopen and hold open the high pressure valve I and the low pressure valve 26, the valves I9, 36

and 21 remaining closed.

High pressure fluid from the pump is now effective to extend the plunger of jack C, through high pressure line 2, intake passages 4 and 4 pastcheck valve 6 which has opened responsive to :a predetermined working l pressure attained when bypass valve 36 closed; high pressure passage 9, valve chamber 9', open high pressure valve jack end of the jack as seen in Figs. 1 and 2.

only when excessive heat expansion of the fluid occurs.

Operation Low pressure uid from the jack returns to the reservoir A through line |8, passage |4', passage 20, open'low pressure valve 26, port I2, cam shaft passage 24, passage 32 and return line 34.

As soon vas the operator has moved vthe cam shaft 4|' to the position for extending the jack, the handle 51 may be released and the cam shaft will be maintained in its operating position by the detent means N as hereinbefore explained, the operator having taken but little time to so move the shaft and being then fr ee to give his attention to other valves or .controls in the manipulation of airplanes.

When the operator releas the handle 51 the Spring 88 urges the ring 83 axially outward, and the cam surfaces 89 bearing on drive pins 8| cause the ring to turn a short distance counterclockwise (say seven degrees of arc) so that the `main open to permitvof release of iluid from the left end of passage 24 as necessary in returning the cam shaft to neutral.

If the operator does not manually eect the return of the cam shaft to neutral, it will automatically return to such position and set the main control valves in neutral when the Jack plunger reaches the end of its extension stroke and the pressure increases due' to immobility ofsaid plunger. Whenthis pressure increase occurs the check valve 66, set to open at slightly higher than normal working pressure, will open and allow the high pressure iluid to pass into the right end of crank shaft passage 24 through vpassage 59, and passage 1B, whereby tot force the cam shaft 4I` to the left and into neutral position.

. Relief of lowA pressure fluid from the left end of cam shaft passage 24 during the return to neutral movement of the cam shaft takesV place through passage 68, passage 58, passage 18, open check valve 1l, passage 18, recess 52, opening 52', "open part of passage 24, located between the ends of the cam shaft, return passage 32 and line 34 to the reservoir B.

As the cam shaft 4| moves back to neutral the rack teeth 53 rotate pinion 5i so that`the shaft 54 and handle 51 will be returned to the neutral position shown in Figs. 4, 6, and 9. As the shaft 54 thus returns to neutral the cam segment 82 on the cam ring 83 is returned to position clear of the push rod 90, whereby the check valve 1I, due to being spring loaded,vwill close.

Return of the cam shaft 4I to neutral position brings the cam portion 46 thereon under the push rod 48 for the by-pass valve 3.6 whereby to open said valve and allow the pressure fluid from the pump to by-pass to valve E as hereinbefore described. As soon as this by-passing operation takes place the pressure in passage 4I is reduced and the spring loaded check valve 6 will close and thereby lock the fluid in the jack cylinder to cause the jack plunger to maintain its extended position. All of the cam shaft controlled valves except by-pass valve 36 are closed as seen in Fig. 1 when the cam shaft 4| is returned to neutra position.

It is not deemed necessary to describe the operation of the valve when manipulated for' retract- 'ing the jack plunger inasmuch as such an operae tion will be obvious with reference to the foreor retraction of the plunger but is returned to neutral position before the pressure has become effective for moving the plungerthrough its full stroke. This requires lcareful judgment of the operator and knowledge as to the usual time required per full plunger stroke, inasmuch as when the cam shaft 4l is thus returned to neutral the whereby to hold the jack plunger in the position short of 4its full lstroke to which it has been moved. By this "cracking" operation of the valve an appreciable nicety of control is afforded and is particularly desirable in operating cowl aps and other devices on an 'airplane which are subject to adjustment in this manner.

I claim:

1. In a valve, a body having a plurality of passages] adapted for operatively vconnecting a uid Pumpfwith a fluid actuateddevice,l 'valve means carried by said body for controlling the ilow of iluid therein including reciprocable members for opening and closing valves of said valve means.

means for operating said valve means to open certain ofsaid passages for controlling the flow is operable as a piston in one of said passages for by-pass valve 36 opens and bv-passes the highj pressure and this allows the lock out check valve 6 to close and trap the fluid in the jack cylinder 75 restoring said valve means to a neutral condition closing said certain passages responsive to fluid pressure attained following the opening of said certain passages, said operating means including cam shaft operating passages leading from said certain passages to opposite ends of the passage in which the cam shaft is operable as a. piston; nor= mally closed spring loaded check valves operating in said cam shaft operating passages to open responsive to a predetermined iiuidpressure at`l sponsive to movement of said ,valve operating means for controlling the' lastnamed valves.

2. In a valve, a body having a plurality of passages for establishing a iiuid circuit between a pump and a uid actuated device, valve means carried by said body for controlling the flow of .f

operating said valve means, for controlling the l hydraulic-operation of said camshaft.

3. In a valve, a body having a plurality of passages for establishing a fluid circuit between a pump and fluid actuated device, valve means carried by said body for controlling the flow of fluid in passages therein, means for operating said valve means to openl certain of the passages for controlling the flow of uid to and from the fluid actuated device, including a reciprocable cam shaft in another of said passages and being man` ually operable for opening said valve means andi thereafter operable as a. piston, responsive to a predetermined uid pressure, for actuating the valve means to close said certain passages;- said operating means also including cam shaft operating passages in said body leading from the said eertainl passages to opposite ends of theA cam shaft passage, normally closed check valves controlling said camshaft operating passages and opening responsive to a predetermined iluid pressure attained in saidcertain passages, return passages in said body leading from opposite ends of said cam shaft passage and adapted for returning duid to said pump, return valves controlling said return passages, and means for selectively opening and closing said return valvesl responsive to movement of said valve operating means.

4. In a valve, 'a body having-a plurality of passages for operatively connecting a hydraulic pump with .a hydraulic jack, valves carried by said body for controlling the flow of fluid in said passa-ges, means for voperating said valves to move them from a neutral position closing those of the passages lfor controlling the ow of fluid to and from said jack into open position, including a reciprocable cam shaft operable manually to.

open the valvesv and thereafter hydraulically operable as a piston in one of said passages for reating passages in said body leading from the passages through which fluid flows for operating the jack to opposite ends of the passage in which the turning said valves to neutral, cam shaft opercam shaft is mounted, normally closed cam shaft operating valves controlling said cam shaft operating passages and opening responsive to a predetermined fluid pressure, fluid return passages in said body leading from opposite ends of the passage containing thecam shaft and adapted for returning fluid to said pump, return valves. controlling said return passages, and means for sages into open position, including a cam shaft in said fluid return passage responsive to a predetermined fiuid pressure following said. opening of said valves for moving said valves to said neutral position, one of the said passages in the body constituting a high pressure intake adapted for connection with the pump and leading to the passages .through which iluid hows for operating jthfe jacln, a by-pass passage leading from said intake passage and through which fluid may be lay-passed from said valve body for operating another jaclr or for return to said reservoir, a bypass valve controlling said by-pass passage and operating responsive to the actuation of said operating means to open when the rst named valves are closed and to close when the first named valves are open, and anormally closed `check valve arranged in said intake to open respons'ive to fluid pressure therein when the bypass valve is closedand to close when the by-pass valve is open. f

6. In a. hydraulic control valve, a body having A' a high pressure intake passage adapted to be connected with a hydraulic pump, jack operating I. passages leading. from saidintake passage and adapted for connection with a hydraulic jack which is to be controlled by said valve, selectively operable valves mounted in said body for controlling said jack operating'passages, a by-pass passage leading fromsaid intake passage and adapted for connection with another hydraulic tion of said intake passage with said jack operating passages in advance of said selectively operable valves, and arranged to remain closed when the by-pass valve is open and to open responsive" to pressure when theby-pass valve is closed, and means for selectively openingand closing said selectively operable valves operating to open said by-pass valve when certain of the selective valves are closed and to permit the by-pass valve to close when certain of saidy selective valves are opened, including a cam shaft common to said` selective and by-pass valves and operated manually toA control certain of said valves and responsive to hydraulic pressure to control certain of said valves including the by-pass valve.

plurality of spring loaded-*valves for controlling said passages, certain of said valves being'arranged'to open responsive to fluid pressure in certain of said passages, and means for opening and closing the other of said valves including a cam member movable in one of said. passages' valve actuating members responsive to movement of said cam member, andvmeans for manually moving said cam member including provision for automatically returning said cam member to a predetermined position upon the opening of one of said pressure responsive valves following a manual movement of said cam member, including return valves for controlling the cam member passage, a handle for manually moving the cam member, and means responsive to movement of the handle for controlling said return valves. p

8. In a control valve for a hydraulic jack or the like, a valve body, valves mounted in said body, and cam means in said body for controli ling said valves including a passage, a cam member reciprocable in said passage responsive to iiuid pressure and manual actuation, aV rotary shaft in said body, and drive means between said cam shaft and rotary shaft for reciprocating said cam member, a sleeve relatively rotatably and axially movably mounted on said shaft, an operating handle for rotating said` sleeve, check axial shifting of said ring for opening :said check valves, other means responsive to relative rota- `tion of the ring and shaft for actuating the push rods to close one check valve and open the other check valve, and means under control of certain 'of the'first named valves for introducing fluid under pressure to either end of said passage for moving the cam member as a piston.

control valve or with a. return line to said pump,

a normally closed spring loaded by-pass valve in said by-pass passage, a normally closed spring loaded check valve'controlling the communicamember, a sleeve relatively rotatably and axially movably mounted on said shaft, an operating handle for rotating said sleeve, check valves for 8 aseaass relieving fluid from oppositeends of the passage in which said member is movable. a drive ring carried by said'sleeve, a disk carried by said shaft, means operating on initial rotation or the l sleeve and the drive ring for shifting said ringv axially and then effecting a drive connection besponsive to relative rotation of the ring and shaft for actuating the check valve operating means to close one check valve and open the other check valve, and means undericontrol of certain of the rst named valves for introducing iluid under pressure to either end of said passage for moving said valve actuating member.

HERMAN RAY mmwoon. 

